diff options
author | Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> | 2013-10-12 01:54:56 +0200 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-10-17 00:36:06 +0200 |
commit | 75d2364ea0cab3a95be3f8d1f8dabd20ac4b1b2a (patch) | |
tree | a09a297c2c763673d9e1658254e4f9e21cbecaf9 | |
parent | PowerCap: Documentation (diff) | |
download | linux-75d2364ea0cab3a95be3f8d1f8dabd20ac4b1b2a.tar.xz linux-75d2364ea0cab3a95be3f8d1f8dabd20ac4b1b2a.zip |
PowerCap: Add class driver
The power capping framework providing a consistent interface between the
kernel and user space that allows power capping drivers to expose their
settings to user space in a uniform way.
The overall design of the framework is described in the documentation
added by the previous patch in this series.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
-rw-r--r-- | drivers/powercap/Kconfig | 19 | ||||
-rw-r--r-- | drivers/powercap/Makefile | 1 | ||||
-rw-r--r-- | drivers/powercap/powercap_sys.c | 683 | ||||
-rw-r--r-- | include/linux/powercap.h | 325 |
4 files changed, 1028 insertions, 0 deletions
diff --git a/drivers/powercap/Kconfig b/drivers/powercap/Kconfig new file mode 100644 index 000000000000..a37055eb5ebc --- /dev/null +++ b/drivers/powercap/Kconfig @@ -0,0 +1,19 @@ +# +# Generic power capping sysfs interface configuration +# + +menuconfig POWERCAP + bool "Generic powercap sysfs driver" + help + The power capping sysfs interface allows kernel subsystems to expose power + capping settings to user space in a consistent way. Usually, it consists + of multiple control types that determine which settings may be exposed and + power zones representing parts of the system that can be subject to power + capping. + + If you want this code to be compiled in, say Y here. + +if POWERCAP +# Client driver configurations go here. + +endif diff --git a/drivers/powercap/Makefile b/drivers/powercap/Makefile new file mode 100644 index 000000000000..6defbc8dc4bf --- /dev/null +++ b/drivers/powercap/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_POWERCAP) += powercap_sys.o diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c new file mode 100644 index 000000000000..c22fa4c78eaa --- /dev/null +++ b/drivers/powercap/powercap_sys.c @@ -0,0 +1,683 @@ +/* + * Power capping class + * Copyright (c) 2013, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc. + * + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/powercap.h> + +#define to_powercap_zone(n) container_of(n, struct powercap_zone, dev) +#define to_powercap_control_type(n) \ + container_of(n, struct powercap_control_type, dev) + +/* Power zone show function */ +#define define_power_zone_show(_attr) \ +static ssize_t _attr##_show(struct device *dev, \ + struct device_attribute *dev_attr,\ + char *buf) \ +{ \ + u64 value; \ + ssize_t len = -EINVAL; \ + struct powercap_zone *power_zone = to_powercap_zone(dev); \ + \ + if (power_zone->ops->get_##_attr) { \ + if (!power_zone->ops->get_##_attr(power_zone, &value)) \ + len = sprintf(buf, "%lld\n", value); \ + } \ + \ + return len; \ +} + +/* The only meaningful input is 0 (reset), others are silently ignored */ +#define define_power_zone_store(_attr) \ +static ssize_t _attr##_store(struct device *dev,\ + struct device_attribute *dev_attr, \ + const char *buf, size_t count) \ +{ \ + int err; \ + struct powercap_zone *power_zone = to_powercap_zone(dev); \ + u64 value; \ + \ + err = kstrtoull(buf, 10, &value); \ + if (err) \ + return -EINVAL; \ + if (value) \ + return count; \ + if (power_zone->ops->reset_##_attr) { \ + if (!power_zone->ops->reset_##_attr(power_zone)) \ + return count; \ + } \ + \ + return -EINVAL; \ +} + +/* Power zone constraint show function */ +#define define_power_zone_constraint_show(_attr) \ +static ssize_t show_constraint_##_attr(struct device *dev, \ + struct device_attribute *dev_attr,\ + char *buf) \ +{ \ + u64 value; \ + ssize_t len = -ENODATA; \ + struct powercap_zone *power_zone = to_powercap_zone(dev); \ + int id; \ + struct powercap_zone_constraint *pconst;\ + \ + if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \ + return -EINVAL; \ + if (id >= power_zone->const_id_cnt) \ + return -EINVAL; \ + pconst = &power_zone->constraints[id]; \ + if (pconst && pconst->ops && pconst->ops->get_##_attr) { \ + if (!pconst->ops->get_##_attr(power_zone, id, &value)) \ + len = sprintf(buf, "%lld\n", value); \ + } \ + \ + return len; \ +} + +/* Power zone constraint store function */ +#define define_power_zone_constraint_store(_attr) \ +static ssize_t store_constraint_##_attr(struct device *dev,\ + struct device_attribute *dev_attr, \ + const char *buf, size_t count) \ +{ \ + int err; \ + u64 value; \ + struct powercap_zone *power_zone = to_powercap_zone(dev); \ + int id; \ + struct powercap_zone_constraint *pconst;\ + \ + if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) \ + return -EINVAL; \ + if (id >= power_zone->const_id_cnt) \ + return -EINVAL; \ + pconst = &power_zone->constraints[id]; \ + err = kstrtoull(buf, 10, &value); \ + if (err) \ + return -EINVAL; \ + if (pconst && pconst->ops && pconst->ops->set_##_attr) { \ + if (!pconst->ops->set_##_attr(power_zone, id, value)) \ + return count; \ + } \ + \ + return -ENODATA; \ +} + +/* Power zone information callbacks */ +define_power_zone_show(power_uw); +define_power_zone_show(max_power_range_uw); +define_power_zone_show(energy_uj); +define_power_zone_store(energy_uj); +define_power_zone_show(max_energy_range_uj); + +/* Power zone attributes */ +static DEVICE_ATTR_RO(max_power_range_uw); +static DEVICE_ATTR_RO(power_uw); +static DEVICE_ATTR_RO(max_energy_range_uj); +static DEVICE_ATTR_RW(energy_uj); + +/* Power zone constraint attributes callbacks */ +define_power_zone_constraint_show(power_limit_uw); +define_power_zone_constraint_store(power_limit_uw); +define_power_zone_constraint_show(time_window_us); +define_power_zone_constraint_store(time_window_us); +define_power_zone_constraint_show(max_power_uw); +define_power_zone_constraint_show(min_power_uw); +define_power_zone_constraint_show(max_time_window_us); +define_power_zone_constraint_show(min_time_window_us); + +/* For one time seeding of constraint device attributes */ +struct powercap_constraint_attr { + struct device_attribute power_limit_attr; + struct device_attribute time_window_attr; + struct device_attribute max_power_attr; + struct device_attribute min_power_attr; + struct device_attribute max_time_window_attr; + struct device_attribute min_time_window_attr; + struct device_attribute name_attr; +}; + +static struct powercap_constraint_attr + constraint_attrs[MAX_CONSTRAINTS_PER_ZONE]; + +/* A list of powercap control_types */ +static LIST_HEAD(powercap_cntrl_list); +/* Mutex to protect list of powercap control_types */ +static DEFINE_MUTEX(powercap_cntrl_list_lock); + +#define POWERCAP_CONSTRAINT_NAME_LEN 30 /* Some limit to avoid overflow */ +static ssize_t show_constraint_name(struct device *dev, + struct device_attribute *dev_attr, + char *buf) +{ + const char *name; + struct powercap_zone *power_zone = to_powercap_zone(dev); + int id; + ssize_t len = -ENODATA; + struct powercap_zone_constraint *pconst; + + if (!sscanf(dev_attr->attr.name, "constraint_%d_", &id)) + return -EINVAL; + if (id >= power_zone->const_id_cnt) + return -EINVAL; + pconst = &power_zone->constraints[id]; + + if (pconst && pconst->ops && pconst->ops->get_name) { + name = pconst->ops->get_name(power_zone, id); + if (name) { + snprintf(buf, POWERCAP_CONSTRAINT_NAME_LEN, + "%s\n", name); + buf[POWERCAP_CONSTRAINT_NAME_LEN] = '\0'; + len = strlen(buf); + } + } + + return len; +} + +static int create_constraint_attribute(int id, const char *name, + int mode, + struct device_attribute *dev_attr, + ssize_t (*show)(struct device *, + struct device_attribute *, char *), + ssize_t (*store)(struct device *, + struct device_attribute *, + const char *, size_t) + ) +{ + + dev_attr->attr.name = kasprintf(GFP_KERNEL, "constraint_%d_%s", + id, name); + if (!dev_attr->attr.name) + return -ENOMEM; + dev_attr->attr.mode = mode; + dev_attr->show = show; + dev_attr->store = store; + + return 0; +} + +static void free_constraint_attributes(void) +{ + int i; + + for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) { + kfree(constraint_attrs[i].power_limit_attr.attr.name); + kfree(constraint_attrs[i].time_window_attr.attr.name); + kfree(constraint_attrs[i].name_attr.attr.name); + kfree(constraint_attrs[i].max_power_attr.attr.name); + kfree(constraint_attrs[i].min_power_attr.attr.name); + kfree(constraint_attrs[i].max_time_window_attr.attr.name); + kfree(constraint_attrs[i].min_time_window_attr.attr.name); + } +} + +static int seed_constraint_attributes(void) +{ + int i; + int ret; + + for (i = 0; i < MAX_CONSTRAINTS_PER_ZONE; ++i) { + ret = create_constraint_attribute(i, "power_limit_uw", + S_IWUSR | S_IRUGO, + &constraint_attrs[i].power_limit_attr, + show_constraint_power_limit_uw, + store_constraint_power_limit_uw); + if (ret) + goto err_alloc; + ret = create_constraint_attribute(i, "time_window_us", + S_IWUSR | S_IRUGO, + &constraint_attrs[i].time_window_attr, + show_constraint_time_window_us, + store_constraint_time_window_us); + if (ret) + goto err_alloc; + ret = create_constraint_attribute(i, "name", S_IRUGO, + &constraint_attrs[i].name_attr, + show_constraint_name, + NULL); + if (ret) + goto err_alloc; + ret = create_constraint_attribute(i, "max_power_uw", S_IRUGO, + &constraint_attrs[i].max_power_attr, + show_constraint_max_power_uw, + NULL); + if (ret) + goto err_alloc; + ret = create_constraint_attribute(i, "min_power_uw", S_IRUGO, + &constraint_attrs[i].min_power_attr, + show_constraint_min_power_uw, + NULL); + if (ret) + goto err_alloc; + ret = create_constraint_attribute(i, "max_time_window_us", + S_IRUGO, + &constraint_attrs[i].max_time_window_attr, + show_constraint_max_time_window_us, + NULL); + if (ret) + goto err_alloc; + ret = create_constraint_attribute(i, "min_time_window_us", + S_IRUGO, + &constraint_attrs[i].min_time_window_attr, + show_constraint_min_time_window_us, + NULL); + if (ret) + goto err_alloc; + + } + + return 0; + +err_alloc: + free_constraint_attributes(); + + return ret; +} + +static int create_constraints(struct powercap_zone *power_zone, + int nr_constraints, + struct powercap_zone_constraint_ops *const_ops) +{ + int i; + int ret = 0; + int count; + struct powercap_zone_constraint *pconst; + + if (!power_zone || !const_ops || !const_ops->get_power_limit_uw || + !const_ops->set_power_limit_uw || + !const_ops->get_time_window_us || + !const_ops->set_time_window_us) + return -EINVAL; + + count = power_zone->zone_attr_count; + for (i = 0; i < nr_constraints; ++i) { + pconst = &power_zone->constraints[i]; + pconst->ops = const_ops; + pconst->id = power_zone->const_id_cnt; + power_zone->const_id_cnt++; + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].power_limit_attr.attr; + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].time_window_attr.attr; + if (pconst->ops->get_name) + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].name_attr.attr; + if (pconst->ops->get_max_power_uw) + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].max_power_attr.attr; + if (pconst->ops->get_min_power_uw) + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].min_power_attr.attr; + if (pconst->ops->get_max_time_window_us) + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].max_time_window_attr.attr; + if (pconst->ops->get_min_time_window_us) + power_zone->zone_dev_attrs[count++] = + &constraint_attrs[i].min_time_window_attr.attr; + } + power_zone->zone_attr_count = count; + + return ret; +} + +static bool control_type_valid(void *control_type) +{ + struct powercap_control_type *pos = NULL; + bool found = false; + + mutex_lock(&powercap_cntrl_list_lock); + + list_for_each_entry(pos, &powercap_cntrl_list, node) { + if (pos == control_type) { + found = true; + break; + } + } + mutex_unlock(&powercap_cntrl_list_lock); + + return found; +} + +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct powercap_zone *power_zone = to_powercap_zone(dev); + + return sprintf(buf, "%s\n", power_zone->name); +} + +static DEVICE_ATTR_RO(name); + +/* Create zone and attributes in sysfs */ +static void create_power_zone_common_attributes( + struct powercap_zone *power_zone) +{ + int count = 0; + + power_zone->zone_dev_attrs[count++] = &dev_attr_name.attr; + if (power_zone->ops->get_max_energy_range_uj) + power_zone->zone_dev_attrs[count++] = + &dev_attr_max_energy_range_uj.attr; + if (power_zone->ops->get_energy_uj) + power_zone->zone_dev_attrs[count++] = + &dev_attr_energy_uj.attr; + if (power_zone->ops->get_power_uw) + power_zone->zone_dev_attrs[count++] = + &dev_attr_power_uw.attr; + if (power_zone->ops->get_max_power_range_uw) + power_zone->zone_dev_attrs[count++] = + &dev_attr_max_power_range_uw.attr; + power_zone->zone_dev_attrs[count] = NULL; + power_zone->zone_attr_count = count; +} + +static void powercap_release(struct device *dev) +{ + bool allocated; + + if (dev->parent) { + struct powercap_zone *power_zone = to_powercap_zone(dev); + + /* Store flag as the release() may free memory */ + allocated = power_zone->allocated; + /* Remove id from parent idr struct */ + idr_remove(power_zone->parent_idr, power_zone->id); + /* Destroy idrs allocated for this zone */ + idr_destroy(&power_zone->idr); + kfree(power_zone->name); + kfree(power_zone->zone_dev_attrs); + kfree(power_zone->constraints); + if (power_zone->ops->release) + power_zone->ops->release(power_zone); + if (allocated) + kfree(power_zone); + } else { + struct powercap_control_type *control_type = + to_powercap_control_type(dev); + + /* Store flag as the release() may free memory */ + allocated = control_type->allocated; + idr_destroy(&control_type->idr); + mutex_destroy(&control_type->lock); + if (control_type->ops && control_type->ops->release) + control_type->ops->release(control_type); + if (allocated) + kfree(control_type); + } +} + +static ssize_t enabled_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + bool mode = true; + + /* Default is enabled */ + if (dev->parent) { + struct powercap_zone *power_zone = to_powercap_zone(dev); + if (power_zone->ops->get_enable) + if (power_zone->ops->get_enable(power_zone, &mode)) + mode = false; + } else { + struct powercap_control_type *control_type = + to_powercap_control_type(dev); + if (control_type->ops && control_type->ops->get_enable) + if (control_type->ops->get_enable(control_type, &mode)) + mode = false; + } + + return sprintf(buf, "%d\n", mode); +} + +static ssize_t enabled_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + bool mode; + + if (strtobool(buf, &mode)) + return -EINVAL; + if (dev->parent) { + struct powercap_zone *power_zone = to_powercap_zone(dev); + if (power_zone->ops->set_enable) + if (!power_zone->ops->set_enable(power_zone, mode)) + return len; + } else { + struct powercap_control_type *control_type = + to_powercap_control_type(dev); + if (control_type->ops && control_type->ops->set_enable) + if (!control_type->ops->set_enable(control_type, mode)) + return len; + } + + return -ENOSYS; +} + +static struct device_attribute powercap_def_attrs[] = { + __ATTR(enabled, S_IWUSR | S_IRUGO, enabled_show, + enabled_store), + __ATTR_NULL +}; + +static struct class powercap_class = { + .name = "powercap", + .dev_release = powercap_release, + .dev_attrs = powercap_def_attrs, +}; + +struct powercap_zone *powercap_register_zone( + struct powercap_zone *power_zone, + struct powercap_control_type *control_type, + const char *name, + struct powercap_zone *parent, + const struct powercap_zone_ops *ops, + int nr_constraints, + struct powercap_zone_constraint_ops *const_ops) +{ + int result; + int nr_attrs; + + if (!name || !control_type || !ops || + nr_constraints > MAX_CONSTRAINTS_PER_ZONE || + (!ops->get_energy_uj && !ops->get_power_uw) || + !control_type_valid(control_type)) + return ERR_PTR(-EINVAL); + + if (power_zone) { + if (!ops->release) + return ERR_PTR(-EINVAL); + memset(power_zone, 0, sizeof(*power_zone)); + } else { + power_zone = kzalloc(sizeof(*power_zone), GFP_KERNEL); + if (!power_zone) + return ERR_PTR(-ENOMEM); + power_zone->allocated = true; + } + power_zone->ops = ops; + power_zone->control_type_inst = control_type; + if (!parent) { + power_zone->dev.parent = &control_type->dev; + power_zone->parent_idr = &control_type->idr; + } else { + power_zone->dev.parent = &parent->dev; + power_zone->parent_idr = &parent->idr; + } + power_zone->dev.class = &powercap_class; + + mutex_lock(&control_type->lock); + /* Using idr to get the unique id */ + result = idr_alloc(power_zone->parent_idr, NULL, 0, 0, GFP_KERNEL); + if (result < 0) + goto err_idr_alloc; + + power_zone->id = result; + idr_init(&power_zone->idr); + power_zone->name = kstrdup(name, GFP_KERNEL); + if (!power_zone->name) + goto err_name_alloc; + dev_set_name(&power_zone->dev, "%s:%x", + dev_name(power_zone->dev.parent), + power_zone->id); + power_zone->constraints = kzalloc(sizeof(*power_zone->constraints) * + nr_constraints, GFP_KERNEL); + if (!power_zone->constraints) + goto err_const_alloc; + + nr_attrs = nr_constraints * POWERCAP_CONSTRAINTS_ATTRS + + POWERCAP_ZONE_MAX_ATTRS + 1; + power_zone->zone_dev_attrs = kzalloc(sizeof(void *) * + nr_attrs, GFP_KERNEL); + if (!power_zone->zone_dev_attrs) + goto err_attr_alloc; + create_power_zone_common_attributes(power_zone); + result = create_constraints(power_zone, nr_constraints, const_ops); + if (result) + goto err_dev_ret; + + power_zone->zone_dev_attrs[power_zone->zone_attr_count] = NULL; + power_zone->dev_zone_attr_group.attrs = power_zone->zone_dev_attrs; + power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group; + power_zone->dev_attr_groups[1] = NULL; + power_zone->dev.groups = power_zone->dev_attr_groups; + result = device_register(&power_zone->dev); + if (result) + goto err_dev_ret; + + control_type->nr_zones++; + mutex_unlock(&control_type->lock); + + return power_zone; + +err_dev_ret: + kfree(power_zone->zone_dev_attrs); +err_attr_alloc: + kfree(power_zone->constraints); +err_const_alloc: + kfree(power_zone->name); +err_name_alloc: + idr_remove(power_zone->parent_idr, power_zone->id); +err_idr_alloc: + if (power_zone->allocated) + kfree(power_zone); + mutex_unlock(&control_type->lock); + + return ERR_PTR(result); +} +EXPORT_SYMBOL_GPL(powercap_register_zone); + +int powercap_unregister_zone(struct powercap_control_type *control_type, + struct powercap_zone *power_zone) +{ + if (!power_zone || !control_type) + return -EINVAL; + + mutex_lock(&control_type->lock); + control_type->nr_zones--; + mutex_unlock(&control_type->lock); + + device_unregister(&power_zone->dev); + + return 0; +} +EXPORT_SYMBOL_GPL(powercap_unregister_zone); + +struct powercap_control_type *powercap_register_control_type( + struct powercap_control_type *control_type, + const char *name, + const struct powercap_control_type_ops *ops) +{ + int result; + + if (!name) + return ERR_PTR(-EINVAL); + if (control_type) { + if (!ops || !ops->release) + return ERR_PTR(-EINVAL); + memset(control_type, 0, sizeof(*control_type)); + } else { + control_type = kzalloc(sizeof(*control_type), GFP_KERNEL); + if (!control_type) + return ERR_PTR(-ENOMEM); + control_type->allocated = true; + } + mutex_init(&control_type->lock); + control_type->ops = ops; + INIT_LIST_HEAD(&control_type->node); + control_type->dev.class = &powercap_class; + dev_set_name(&control_type->dev, name); + result = device_register(&control_type->dev); + if (result) { + if (control_type->allocated) + kfree(control_type); + return ERR_PTR(result); + } + idr_init(&control_type->idr); + + mutex_lock(&powercap_cntrl_list_lock); + list_add_tail(&control_type->node, &powercap_cntrl_list); + mutex_unlock(&powercap_cntrl_list_lock); + + return control_type; +} +EXPORT_SYMBOL_GPL(powercap_register_control_type); + +int powercap_unregister_control_type(struct powercap_control_type *control_type) +{ + struct powercap_control_type *pos = NULL; + + if (control_type->nr_zones) { + dev_err(&control_type->dev, "Zones of this type still not freed\n"); + return -EINVAL; + } + mutex_lock(&powercap_cntrl_list_lock); + list_for_each_entry(pos, &powercap_cntrl_list, node) { + if (pos == control_type) { + list_del(&control_type->node); + mutex_unlock(&powercap_cntrl_list_lock); + device_unregister(&control_type->dev); + return 0; + } + } + mutex_unlock(&powercap_cntrl_list_lock); + + return -ENODEV; +} +EXPORT_SYMBOL_GPL(powercap_unregister_control_type); + +static int __init powercap_init(void) +{ + int result = 0; + + result = seed_constraint_attributes(); + if (result) + return result; + + result = class_register(&powercap_class); + + return result; +} + +device_initcall(powercap_init); + +MODULE_DESCRIPTION("PowerCap sysfs Driver"); +MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/powercap.h b/include/linux/powercap.h new file mode 100644 index 000000000000..4e250417ee30 --- /dev/null +++ b/include/linux/powercap.h @@ -0,0 +1,325 @@ +/* + * powercap.h: Data types and headers for sysfs power capping interface + * Copyright (c) 2013, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc. + * + */ + +#ifndef __POWERCAP_H__ +#define __POWERCAP_H__ + +#include <linux/device.h> +#include <linux/idr.h> + +/* + * A power cap class device can contain multiple powercap control_types. + * Each control_type can have multiple power zones, which can be independently + * controlled. Each power zone can have one or more constraints. + */ + +struct powercap_control_type; +struct powercap_zone; +struct powercap_zone_constraint; + +/** + * struct powercap_control_type_ops - Define control type callbacks + * @set_enable: Enable/Disable whole control type. + * Default is enabled. But this callback allows all zones + * to be in disable state and remove any applied power + * limits. If disabled power zone can only be monitored + * not controlled. + * @get_enable: get Enable/Disable status. + * @release: Callback to inform that last reference to this + * control type is closed. So it is safe to free data + * structure associated with this control type. + * This callback is mandatory if the client own memory + * for the control type. + * + * This structure defines control type callbacks to be implemented by client + * drivers + */ +struct powercap_control_type_ops { + int (*set_enable) (struct powercap_control_type *, bool mode); + int (*get_enable) (struct powercap_control_type *, bool *mode); + int (*release) (struct powercap_control_type *); +}; + +/** + * struct powercap_control_type- Defines a powercap control_type + * @name: name of control_type + * @dev: device for this control_type + * @idr: idr to have unique id for its child + * @root_node: Root holding power zones for this control_type + * @ops: Pointer to callback struct + * @node_lock: mutex for control type + * @allocated: This is possible that client owns the memory + * used by this structure. In this case + * this flag is set to false by framework to + * prevent deallocation during release process. + * Otherwise this flag is set to true. + * @ctrl_inst: link to the control_type list + * + * Defines powercap control_type. This acts as a container for power + * zones, which use same method to control power. E.g. RAPL, RAPL-PCI etc. + * All fields are private and should not be used by client drivers. + */ +struct powercap_control_type { + struct device dev; + struct idr idr; + int nr_zones; + const struct powercap_control_type_ops *ops; + struct mutex lock; + bool allocated; + struct list_head node; +}; + +/** + * struct powercap_zone_ops - Define power zone callbacks + * @get_max_energy_range_uj: Get maximum range of energy counter in + * micro-joules. + * @get_energy_uj: Get current energy counter in micro-joules. + * @reset_energy_uj: Reset micro-joules energy counter. + * @get_max_power_range_uw: Get maximum range of power counter in + * micro-watts. + * @get_power_uw: Get current power counter in micro-watts. + * @set_enable: Enable/Disable power zone controls. + * Default is enabled. + * @get_enable: get Enable/Disable status. + * @release: Callback to inform that last reference to this + * control type is closed. So it is safe to free + * data structure associated with this + * control type. Mandatory, if client driver owns + * the power_zone memory. + * + * This structure defines zone callbacks to be implemented by client drivers. + * Client drives can define both energy and power related callbacks. But at + * the least one type (either power or energy) is mandatory. Client drivers + * should handle mutual exclusion, if required in callbacks. + */ +struct powercap_zone_ops { + int (*get_max_energy_range_uj) (struct powercap_zone *, u64 *); + int (*get_energy_uj) (struct powercap_zone *, u64 *); + int (*reset_energy_uj) (struct powercap_zone *); + int (*get_max_power_range_uw) (struct powercap_zone *, u64 *); + int (*get_power_uw) (struct powercap_zone *, u64 *); + int (*set_enable) (struct powercap_zone *, bool mode); + int (*get_enable) (struct powercap_zone *, bool *mode); + int (*release) (struct powercap_zone *); +}; + +#define POWERCAP_ZONE_MAX_ATTRS 6 +#define POWERCAP_CONSTRAINTS_ATTRS 8 +#define MAX_CONSTRAINTS_PER_ZONE 10 +/** + * struct powercap_zone- Defines instance of a power cap zone + * @id: Unique id + * @name: Power zone name. + * @control_type_inst: Control type instance for this zone. + * @ops: Pointer to the zone operation structure. + * @dev: Instance of a device. + * @const_id_cnt: Number of constraint defined. + * @idr: Instance to an idr entry for children zones. + * @parent_idr: To remove reference from the parent idr. + * @private_data: Private data pointer if any for this zone. + * @zone_dev_attrs: Attributes associated with this device. + * @zone_attr_count: Attribute count. + * @dev_zone_attr_group: Attribute group for attributes. + * @dev_attr_groups: Attribute group store to register with device. + * @allocated: This is possible that client owns the memory + * used by this structure. In this case + * this flag is set to false by framework to + * prevent deallocation during release process. + * Otherwise this flag is set to true. + * @constraint_ptr: List of constraints for this zone. + * + * This defines a power zone instance. The fields of this structure are + * private, and should not be used by client drivers. + */ +struct powercap_zone { + int id; + char *name; + void *control_type_inst; + const struct powercap_zone_ops *ops; + struct device dev; + int const_id_cnt; + struct idr idr; + struct idr *parent_idr; + void *private_data; + struct attribute **zone_dev_attrs; + int zone_attr_count; + struct attribute_group dev_zone_attr_group; + const struct attribute_group *dev_attr_groups[2]; /* 1 group + NULL */ + bool allocated; + struct powercap_zone_constraint *constraints; +}; + +/** + * struct powercap_zone_constraint_ops - Define constraint callbacks + * @set_power_limit_uw: Set power limit in micro-watts. + * @get_power_limit_uw: Get power limit in micro-watts. + * @set_time_window_us: Set time window in micro-seconds. + * @get_time_window_us: Get time window in micro-seconds. + * @get_max_power_uw: Get max power allowed in micro-watts. + * @get_min_power_uw: Get min power allowed in micro-watts. + * @get_max_time_window_us: Get max time window allowed in micro-seconds. + * @get_min_time_window_us: Get min time window allowed in micro-seconds. + * @get_name: Get the name of constraint + * + * This structure is used to define the constraint callbacks for the client + * drivers. The following callbacks are mandatory and can't be NULL: + * set_power_limit_uw + * get_power_limit_uw + * set_time_window_us + * get_time_window_us + * get_name + * Client drivers should handle mutual exclusion, if required in callbacks. + */ +struct powercap_zone_constraint_ops { + int (*set_power_limit_uw) (struct powercap_zone *, int, u64); + int (*get_power_limit_uw) (struct powercap_zone *, int, u64 *); + int (*set_time_window_us) (struct powercap_zone *, int, u64); + int (*get_time_window_us) (struct powercap_zone *, int, u64 *); + int (*get_max_power_uw) (struct powercap_zone *, int, u64 *); + int (*get_min_power_uw) (struct powercap_zone *, int, u64 *); + int (*get_max_time_window_us) (struct powercap_zone *, int, u64 *); + int (*get_min_time_window_us) (struct powercap_zone *, int, u64 *); + const char *(*get_name) (struct powercap_zone *, int); +}; + +/** + * struct powercap_zone_constraint- Defines instance of a constraint + * @id: Instance Id of this constraint. + * @power_zone: Pointer to the power zone for this constraint. + * @ops: Pointer to the constraint callbacks. + * + * This defines a constraint instance. + */ +struct powercap_zone_constraint { + int id; + struct powercap_zone *power_zone; + struct powercap_zone_constraint_ops *ops; +}; + + +/* For clients to get their device pointer, may be used for dev_dbgs */ +#define POWERCAP_GET_DEV(power_zone) (&power_zone->dev) + +/** +* powercap_set_zone_data() - Set private data for a zone +* @power_zone: A pointer to the valid zone instance. +* @pdata: A pointer to the user private data. +* +* Allows client drivers to associate some private data to zone instance. +*/ +static inline void powercap_set_zone_data(struct powercap_zone *power_zone, + void *pdata) +{ + if (power_zone) + power_zone->private_data = pdata; +} + +/** +* powercap_get_zone_data() - Get private data for a zone +* @power_zone: A pointer to the valid zone instance. +* +* Allows client drivers to get private data associate with a zone, +* using call to powercap_set_zone_data. +*/ +static inline void *powercap_get_zone_data(struct powercap_zone *power_zone) +{ + if (power_zone) + return power_zone->private_data; + return NULL; +} + +/** +* powercap_register_control_type() - Register a control_type with framework +* @control_type: Pointer to client allocated memory for the control type +* structure storage. If this is NULL, powercap framework +* will allocate memory and own it. +* Advantage of this parameter is that client can embed +* this data in its data structures and allocate in a +* single call, preventing multiple allocations. +* @control_type_name: The Name of this control_type, which will be shown +* in the sysfs Interface. +* @ops: Callbacks for control type. This parameter is optional. +* +* Used to create a control_type with the power capping class. Here control_type +* can represent a type of technology, which can control a range of power zones. +* For example a control_type can be RAPL (Running Average Power Limit) +* IntelĀ® 64 and IA-32 Processor Architectures. The name can be any string +* which must be unique, otherwise this function returns NULL. +* A pointer to the control_type instance is returned on success. +*/ +struct powercap_control_type *powercap_register_control_type( + struct powercap_control_type *control_type, + const char *name, + const struct powercap_control_type_ops *ops); + +/** +* powercap_unregister_control_type() - Unregister a control_type from framework +* @instance: A pointer to the valid control_type instance. +* +* Used to unregister a control_type with the power capping class. +* All power zones registered under this control type have to be unregistered +* before calling this function, or it will fail with an error code. +*/ +int powercap_unregister_control_type(struct powercap_control_type *instance); + +/* Zone register/unregister API */ + +/** +* powercap_register_zone() - Register a power zone +* @power_zone: Pointer to client allocated memory for the power zone structure +* storage. If this is NULL, powercap framework will allocate +* memory and own it. Advantage of this parameter is that client +* can embed this data in its data structures and allocate in a +* single call, preventing multiple allocations. +* @control_type: A control_type instance under which this zone operates. +* @name: A name for this zone. +* @parent: A pointer to the parent power zone instance if any or NULL +* @ops: Pointer to zone operation callback structure. +* @no_constraints: Number of constraints for this zone +* @const_ops: Pointer to constraint callback structure +* +* Register a power zone under a given control type. A power zone must register +* a pointer to a structure representing zone callbacks. +* A power zone can be located under a parent power zone, in which case @parent +* should point to it. Otherwise, if @parent is NULL, the new power zone will +* be located directly under the given control type +* For each power zone there may be a number of constraints that appear in the +* sysfs under that zone as attributes with unique numeric IDs. +* Returns pointer to the power_zone on success. +*/ +struct powercap_zone *powercap_register_zone( + struct powercap_zone *power_zone, + struct powercap_control_type *control_type, + const char *name, + struct powercap_zone *parent, + const struct powercap_zone_ops *ops, + int nr_constraints, + struct powercap_zone_constraint_ops *const_ops); + +/** +* powercap_unregister_zone() - Unregister a zone device +* @control_type: A pointer to the valid instance of a control_type. +* @power_zone: A pointer to the valid zone instance for a control_type +* +* Used to unregister a zone device for a control_type. Caller should +* make sure that children for this zone are unregistered first. +*/ +int powercap_unregister_zone(struct powercap_control_type *control_type, + struct powercap_zone *power_zone); + +#endif |